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A20 takes on tumors: tumor suppression by an ubiquitin-editing enzyme

Barbara A Malynn1, Averil Ma

  • 1Program in Biomedical Sciences, Program in Biological Sciences, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA.

The Journal of Experimental Medicine
|April 22, 2009
PubMed

Insights

Researchers discovered mutations in the TNFAIP3 gene, which produces the NF-kappaB inhibitor A20, in specific B cell cancers. This finding highlights A20

Area of Science:

  • Oncology
  • Molecular Biology
  • Immunology

Background:

  • B cell cancers often involve abnormal NF-kappaB signaling.
  • The NF-kappaB pathway regulates immune responses and cell survival.

Purpose of the Study:

  • To investigate the role of TNFAIP3 mutations in B cell lymphomas.
  • To identify potential tumor suppressor functions related to NF-kappaB inhibition.

Main Methods:

  • Somatic mutation analysis of the TNFAIP3 gene.
  • Analysis of patient samples from Hodgkin lymphomas and primary mediastinal lymphomas.

Main Results:

  • Somatic mutations in TNFAIP3 were identified in Hodgkin lymphomas and primary mediastinal lymphomas.
  • These mutations affect the expression or function of the A20 protein.

Conclusions:

  • The TNFAIP3 gene, encoding A20, is somatically mutated in specific B cell lymphomas.
  • A20 functions as a tumor suppressor protein, and its dysregulation contributes to lymphomagenesis.

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